Question

The least no. Of terms of the G.P 4, 8, 16------ that must be taken for their sum to exeed 500 is

Answer 1

Answer:

7

Step-by-step explanation:

a=4

a2= 8

a2/a = 2 = r

s=a(r^n-1)/r-1

s=4(2^n-1)(2-1)

s=4.2^n -4~500

s=2^n+2 ~504

s=2^n+2~2^9

n+2=9

n=7